Hella lighting (4kq) -- cops search?

[Lawrence C Leung]

Never looked carefully enough at it, but you are right. So, I wonder what
those "Sodium Blue lamps really are?

LL - NY

On Sun, 24 Dec 2000 08:55:57+0000 quk at isham-research.freeserve.co.uk
writes:
>
>> Confuses me, too, however if Sodium lamps are good for certain
>> "vegetables" I do know that most plants tend to respond well to 
>yellow
>> and near (but not actual UV, that's a killer!) UV light. Near UV 
>light
>> has lots of energy, but some it tends to get reflected by the blue 
>in the
>> chlorophyl, and Yellow is well absorbed by green (green is 
>reflected,
>> hence that why we see plants as green). So, it makes more sense for 
>the
>> Sodium lamps to be yellow, not "Sodium blue". IMHO, if they are 
>blue,
>> it's by tinting the bulb, which means lots of light get's filtered 
>out
>> and wasted.
>
>'Lots'?
>
>Ever looked at the spectrum of a sodium lamp?  The main line 
>(actually
>a twin line - good luck at splitting it) accounts for 98%(?) of the
>radiated energy.  There are some other equally specific lines, and 
>that's
>it.  A _good_ blue filter would result in total darkness - a tiny
>fraction of 1% would get through.
>
>--
> Phil Payne
> http://www.isham-research.freeserve.co.uk/quattro
> Phone +44 7785 302803   Fax: +44 7785 309674